Thermisia Castle is located on a hill, north of the village of the same name in Argolis. Built during the Venetian occupation, in the 12th century, the castle of Thermisia is situated on top of an imposing rock, almost 300 meters high, facing the lagoon. The first mention of the castle of Thermisia is found around 1347. Almost forty years later, it was captured by Theodore Palaiologos, who in turn handed it over to the Venetians. In 1686, the castle protected the salt marshes of the Thermisia lagoon from enemies and pirates. Moreover, together with that of Ermioni, it was considered one of the strongest fortresses in the Frankish era. In 1715, its Venetian owners blew it up in order not to give it to the opposing victor. The castle of Thermisia is also haunted by the legend of the princess who jumped off its cliffs to avoid surrendering it to the Turks, and it was from there that it was given the alternative name of ‘the castle of Oria’. Today, the gate of the castle of Thermisia it is not preserved, but at least a large part of the wall with its battlements is preserved. Behind this wall, the visitor can also see a circulated cistern, while a small part of a sanctuary probably built in the 14th century is also preserved. Access to the castle of Thermisia is very easy either by road from the nearby town of Ermioni and its coastal settlements, such as Plepi, Iliokastro, and Achladitsa, or on foot from the village of the same name.